Sluggish crops face slug attack
Shrinking day length is exacerbating this autumn’s exceptional slug risk, slowing establishment of late-drilled crops and leaving them vulnerable to longer periods of attack from night-feeding slugs, warns Masstock.
"As drilling is pushed further into the autumn and days get shorter and cooler, we’re not seeing the growth spurt that we’re used to from newly-drilled crops," says Clare Bend, Masstock’s technical manager. "And, following ideal breeding conditions for slug multiplication during the summer, populations are higher than we’ve seen for years."
Almost an hour of daylight is lost for every fortnight the drilling date is pushed back into the autumn, with daylight hours reducing from more than 13 hours on September 1st to just 11 hours on October 1st. Combined with cooler temperatures, these shorter day-lengths present poorer growing conditions and slow crop growth while allowing slugs more time to feed.
"It is very difficult to get a good well-consolidated seedbed," says Ms Bend. "Medium and heavy soils are still wet, cloddy and smeared which is making integrated control more difficult and putting extra pressure on chemistry."
Masstock advises growers to monitor populations, exercise cultural control as much as possible and to use a good quality slug pellet. "Persistence is the key issue this season," says Ms Bend. "Lesser quality pellets are not standing up to these difficult conditions and growers are having to re-apply pellets or even having to re-drill crops.
"It is in autumn conditions such as these that pellet manufacturers’ claims for persistence are most valued. High quality pellets, such as TDS Metarex Amba, stand up to the wet autumn conditions and offer lasting control. They are also more capable of being spread to an even width, because they’re more robust and less likely to crumble.
At just 4% metaldehyde, TDS Metarex Amba also minimises environmental impact and helps reduce the risk of water contamination, she says. "A maximum dose rate of 7kg/ha of TDS Metarex Amba pellets will result in a net dose of 280g/ha of active – far less than a standard mini.
"Stewardship of slug pellets is essential – they are pesticides and must be treated as such," she emphasises. "Only apply in conditions in which you would spray and take care when washing down machinery to avoid contamination in surface waters, ditches or drains."
